Abstract: A heterodyne receiver converts a received high frequency signal into an intermediate frequency signal and demodulates a base band signal from a intermediate frequency signal. Low-pass filters cut the high frequency components of the baseband signal, and AD converters sample the output signal of those low-pass filters, convert them to a digital signal and input them to a Fourier transformer. An intermediate frequency determining part determines the intermediate frequency so that the spectrum when the intermediate frequency signal being inputted to the AD converter is under-sampled appears within a subcarrier band not used in OFDM transmission.

Abstract: A radio receiver includes a branching unit, a first gain-control system, a second-gain control system, and a signal processing unit. The branching unit branches a radio signal received by the radio receiver into two signals. The first-gain control system performs a gain control of a pilot signal in one of branched signals, and the second gain control system performs a gain control of a data signal in another of the branched signals. The signal processing unit synchronizes frames in the received radio signal. The signal processing unit outputs a gain signal to each of the first gain-control system and the second gain-control system. The first gain-control system and the second gain-control system perform the gain controls based on the gain signal.

Abstract: In a radio base station transceiver sub-system including a radio block, a plurality of base band processing blocks, and a channel allocation control block, the channel allocation control block calculates, for each base band signal processing block, the processing load, converted to a weight value, of all the channels allocated thereto or the ratio of said processing load and processing capability, converted to a weight value, of the base band signal processing block and allocates the traffic channel or the control channel to a base band signal processing block where the processing load or the ratio is small.

Abstract: Object: To provide a time stamping system for electronic documents making it possible to easily provide a time stamp certifying date and time of a document prepared with general purpose document preparation software and also to easily and accurately verify the time data and a program medium for the same.

Abstract: In a radio base station transceiver sub-system including a radio block, a plurality of base band processing blocks, and a channel allocation control block, the channel allocation control block calculates, for each base band signal processing block, the processing load, converted to a weight value, of all the channels allocated thereto or the ratio of said processing load and processing capability, converted to a weight value, of the base band signal processing block and allocates the traffic channel or the control channel to a base band signal processing block where the processing load or the ratio is small.